<?php
/**
 * COPYRIGHT © 2022 JOHN PEARCEY
 * All rights reserved
*/

const BASE64_DIGITS = '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz$_';

if (version_compare( PHP_VERSION, '8', '<') ){	
	include_once __DIR__ . "/common-pre-v8.php";
}

function getStackTrace(){
	try{
		throw new Exception;
	}catch( Exception $e ){
		return $e->getTraceAsString();
	}
}

/**
 * e.g. split 
 * 	../db/stanhopetest/img/img_52548
 * into 
 * [ ../db/stanhopetest/img/ , img_52548 ]
 * 
 */
function split_file_path( $ffn ){
	$fn = basename( $ffn ); 				// img_52548
	//$fp = substr( $ffn, 0, strlen($ffn) - strlen($fn) );
	$fp = dirname( $ffn ) . '/';
	return [ $fp, $fn ];
}

/**
 * Returns true if it is possible to create this directory on the file system.
 * Includes the possibility of multiple directories.
 */
function is_creatable_dir( $dirs ){
	$dir = $dirs; 
	while(!file_exists($dir)){
		$dir = dirname( $dir ); 
	}
	return is_writable($dir);
}

/**
 * Function to make directories and actually SET the permissions
 * https://www.php.net/manual/en/function.chmod.php
 * 
 * $perms is an octal number
 * 	e.g. mkdirs( $dir, 02770 ); //770 and g+s
 */
function mkdirs( $dirs, $perms ){
	$dir = $dirs; 
	while(!file_exists($dir)){
		$dir = dirname( $dir ); 
	}
	$rootDir = $dir;
	if(!file_exists($dirs)) mkdir( $dirs, 0750, true );	//perms not always set
	$dir = $dirs; 
	while( $dir!=$rootDir) {
		chmod( $dir, $perms );
		$dir = dirname( $dir ); 
	}
}

/**
 * Return the contents of a url as a string using the curl functions.
 */
function getContentsFromUrl( $url ){
	
	$ch = curl_init( $url );
	//$fp = fopen("example_homepage.txt", "w");
	$fp = tmpfile();
	
	curl_setopt($ch, CURLOPT_FILE, $fp);
	curl_setopt($ch, CURLOPT_HEADER, 0);

	curl_exec($ch);
	$c_err = curl_error($ch);
	curl_close($ch);
	if($c_err) {
		error_log( $c_err );
		fclose($fp);
		return;
	}

	$f_path = stream_get_meta_data($fp)['uri'];
	$rtn = file_get_contents( $f_path );
	fclose($fp);

	return $rtn;
}

/**
 * Set the given key-value pair.
 * 
 * Returns the record ID.
 */
function params_set( $key, $val ) {

	$rec = R::findOne( 'params', 'pkey=?', [$key] );
	if($rec) {
		$rec->pval = $val;
		R::store( $rec );
		return $rec->id;
	}

	$rec = R::dispense( 'params' );
	$rec->pkey = $key;
	$rec->pval = $val;
	return R::store( $rec );
}

function params_get_date( $key ){
	return strtotime( params_get($key) );
}

/**
 * Returns the value for the given key. Returns null if no such key exists.
 */
function params_get( $key ){

	$rec = R::findOne( 'params', 'pkey=?', [$key] );
	if(!$rec) return null;
	return $rec->pval;
}

/**
 * A novel way of creating a unique ID each time a call is made. The new ID is
 * returned.
 * 
 * e.g.
 * This can be used to give a client which might want to create temporary unique IDs. It is
 * called once per client refresh and used to ensure uniqueness of certain CSS data points.
 */
function params_unique( ) {

	$rec = R::dispense( 'params' );
	$rec->pkey = 'unique';
	$id = R::store( $rec );	
	R::exec( "delete from params where id<$id and pkey='unique'" );
	return $id;
}

/**
 * Return a string representation for the given dom node suitable for debugging.
 */
function getNodeString( $rmElem ){
	
	if($rmElem==null) return "Element is null";
	$str="";
	if( $rmElem->nodeType==XML_ELEMENT_NODE){
		$str .= $rmElem->nodeName;
		$a = $rmElem->getAttribute("shb_compid");
		if($a){
			$str .= " shb_compid=$a";
		}
	}else{
		$str .= 'type = '.$rmElem->nodeType;
	}
	return $str;
}

/**
 * Simple logger to write to a file. Using php error_log distorts all crlf pairs. This
 * is a pain when you're trying to preserve them in html.
 */
function mylog( $msg ){
	
	global $logging_on;
	
	if(!$logging_on) return;
	$p = __DIR__ . "/../../shb.log";
	$h = fopen( $p, "a");  
	if($h===false) return;
	fwrite( $h, "$msg\n");
	fclose($h);

}

function generateNonce( $digitCount = 12 ){
	// e.g. 422466a05f24b09c978fa1f6
	return bin2hex( random_bytes($digitCount) );
}

/**
 * Generate a randon username starting with a letter and containing only letters and numbers.
 */
function generateRndUserName( $digitCount = 10 ){
	$l1 = generateRndStrUsing( 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz', 1 );
	return $l1 . generateRndStrUsing( BASE64_DIGITS, $digitCount-1 );
}

/**
 * Generate a randon password with letters and numbers and some funny stuff.
 */
function generateRndPwd( $digitCount = 10 ){	
	return generateRndStrUsing( '0123456789_!"£$%^&*()_-|\?/<>#~ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz', $digitCount );	
}

/**
 * Generate a randon string of asc char. Default consisting of only [0-9][a-z][A-Z]
 */
function generateRndStrUsing( $using=BASE64_DIGITS, $digitCount = 8 ){
	
	$str = '';
	$maxlen = strlen($using);
	for($i=0; $i<$digitCount; $i++){
		$iv = random_int(0, $maxlen-1);
		$str .= mb_substr( $using, $iv, 1);	//use mb_substr because £ is not and asc char!
	}
	return $str;
}


/**
 * Remove all html from the given string returning just the text content.
 */
function removeHtml( $str ){
	//txt =	txt.replace(/<div>/gi, '\n');	
	return preg_replace( '/<\/?[^>]+>/i', '', $str );
}

function getHtmlOkAsString( $data ){
	$data = json_encode( $data );
	return "[\"OK\", $data ]";		
}
	
function sendHtmlOk( $data="" ){
	echo getHtmlOkAsString( $data );
}

/**
 * An effort to rectify my previously ill-thought out return encoding. You do not
 * need to encode the data before calling this method. Any arrays will be json encoded.
 */
function sendHtmlOk_WithData( $data ){
	$data = json_encode( $data );
	echo "[\"OK\", $data ]";	
}

function getHtmlErrorAsString( $strErrDesc = "--blank--" ){
	$data = json_encode( $strErrDesc );
	return "[\"Error\", $data]";
}

function sendHtmlError( $strErrDesc = "--blank--" ){
	$rtn = getHtmlErrorAsString( $strErrDesc );
	mylog( $rtn );
	echo $rtn;
}

/**
 * 
 */
function getAttForPath( $name, $prefPath, $path){
	return "$name = \"$prefPath/$path\"";
}

global $g_pub_path;

/**
 * If the browser=true, the file returned will be correct for adding to an href or src attribute so that the
 * browser will find the link.
 */
function getDirForType( $filetype='html', $browser=false, $userid=-1 ){
	
	global $g_pub_path;
		
	if($g_pub_path==null){
		$g_pub_path = params_get('pub_path');
		if($g_pub_path==null){
			throw new Exception("Publishing now requires a valid key('pub_path') in the params table for the publishing output path");
		}
		
		if(str_ends_with( $g_pub_path, '/') ) $g_pub_path = substr($g_pub_path, 0, strlen($g_pub_path)-1 );
		
		//ensure all the directories exist
		createUserDir( 'img', $userid );
		createUserDir( 'css', $userid );
		createUserDir( 'html', $userid );
		createUserDir( 'js', $userid );
		
	}

	return getDirForType_( $filetype, $browser, $userid );

}

function createUserDir( $dName, $userid ){
	
	if(!file_exists(getDirForType_( $dName, false, $userid ))) {
		$dir = getDirForType_( $dName, false, $userid );
		error_log("common.php: createUserDir: $dir");
		mkdir( $dir, 0770, true);	
	}
}

/**
 * Part of the new path handling system is to sepatate out path names from real files
*/
function mkdirIfNotExists( $d ){
	if(!file_exists( $d ) ) {
		error_log("common.php: createUserDir: $d");
		mkdir( $d, 0770, true );	
	}
}

/**
 * For the moment, call getDirForType and not this function. In time, the setup routine will make the directories
 * and eliminate the need for the check during a user session.
 * 
 * If the browser flag is set, we assuming a document root sub-dir. But in time, this will need to also cater for
 * a site serving the g_pub_path as root (wrt the browser).
 * 
 */
function getDirForType_( $filetype, $browser, $userid ){	
	
	global $g_pub_path;
	$strPath = $g_pub_path;	
	
	
	if($userid>0){
		$strPath .= "_dbg_$userid";		
	}
	
	switch($filetype){
	
	case 'img':
		if($browser) return "/$strPath/img/";	
		return fxdPth( "$strPath/img/" );		

	case 'js':
		if($browser) return "/$strPath/js/";	
		return fxdPth( "$strPath/js/" );		

	case 'css':
		if($browser) return "/$strPath/css/";
		return fxdPth( "$strPath/css/" );		
					
	case 'html':
	default:
		if($browser) return "/$strPath/";
		return fxdPth( "$strPath/" );
		
	}	
}


//NO white-space